Police hold shields following running battles with supporters of the opposition Sierra Leone People’s Party in the Goderich neighborhood of Freetown, Sierra Leone, March 7, 2018. (J. Patinkin/VOA)

Supporters of the opposition Sierra Leone People’s Party walk after clashing with police outside party headquarters in Freetown’s Goderich neighborhood, March 7, 2018. (J. Patinkin/VOA)

Sierra Leone’s main opposition leader called for calm Wednesday night after his supporters engaged in running street battles with police, resulting in at least one injury at the end of an otherwise peaceful day of polling in the West African nation.

“I want every Sierra Leonean to behave themselves in a very peaceful manner so that we can have a peaceful election once in our lifetime,” Julius Maada Bio told reporters at Sierra Leone People’s Party headquarters in Freetown’s posh Goderich neighborhood, where he was holed up at dusk after his supporters clashed with police on the street.

“We hope this does not mar the whole election, which has been relatively smooth,” said Bio, a retired general who briefly seized power in a 1996 coup before handing power to civilian authorities.

Sierra Leone held general elections Wednesday in what analysts said was one of the most hotly contested races in the country’s history. Bio was running for president against Samura Kamara of the ruling All People’s Congress and 14 other candidates. The current president, Ernest Bai Koromo of the APC, must step down after serving two terms.

The vote went mostly smoothly across the country, but after polls closed, tensions rose in Goderich following an alleged incident outside the SLPP headquarters, where party officials said they were conducting a vote tally.

Bio accused police of trying to enter the compound without a warrant and putting him under “siege.” He said police accused him of “hacking” and threatened to use tear gas and force to enter. Bio rejected the hacking allegation.

SLPP supporters then amassed in the streets, facing off against police carrying shields who had deployed. Police used pepper spray and electric shocks to disperse the growing crowd, and SLPP supporters then began throwing rocks and glass bottles at police. Police responded by throwing rocks back, prompting running battles.

At least one SLPP supporter was injured.

Claude Robert, with a gash on his forehead, said police hit him as he tried to block them from entering the SLPP compound.

A few armed soldiers were also on the scene but did not participate in the melee.

VOA said it was unable to reach police for comment, but officers withdrew from outside SLPP headquarters after the skirmishes.

As the clashes died down, Bio met with police and election observers, including former Nigeria President Goodluck Jonathan, head of the African Union observer mission to Sierra Leone.

Sierra Leone has enjoyed relative peace since its bloody civil war ended 15 years ago, but the country has been hit by crises recently, including the devastating 2014 Ebola outbreak and a deadly mudslide last year.

The APC has been accused of responding poorly to those disasters and of corruption. The party’s supporters point to newly built roads and electricity connections during Koromo’s decade in power.